I. Field of the Invention
The present invention relates generally to syringe pumps, and in particular to a programmable, battery-charged syringe pump for the controlled addition of reagents to a chemical reaction, which can adapt the rate of addition of reagent according to changes in physical properties of the reaction mixture such as reaction temperature and pH content.
II. Description of the Prior Art
In small-scale chemical reactions (e.g. laboratory research), the controlled addition of reagents to a chemical reaction is often accomplished by use of disposable plastic syringes. A scientist may choose to fill a disposable syringe with the desired reagent and then manually control the rate of addition of the reagent into a reaction mixture. While this manual method may afford good control of the addition rate of the reagent, it requires “hands-on” syringe operation to inject small portions of the reagent over time, resulting in poor use of valuable labor time. Addition funnels have long been used to control addition of chemical reagent to a reaction mixture, but they give unreliable control, require “hands-on” adjustment during the addition phase, and offer no direct control of the reaction mixture.
In medium-scale chemical reactions utilizing between 1-20 liters of reaction mixture (e.g. process development), metering valves and analytical balances are sometimes used in conjunction with either pressure or a vacuum to transfer large volumes of liquid reagents into the reaction mixture. This method requires significant monitoring by the chemist and gives poor control of the addition rate. Liquid transfer pumps (i.e. piston pumps) are sometimes used in this process, but these piston pumps are generally unreliable, being prone to leakage and seizure during operation.
It is known that the rate of addition of chemical reagent to a reaction mixture can be adequately controlled by use of programmable syringe pumps. Most available prior art programmable syringe pump devices are large (requiring up to a square ft. of bench top space), expensive, and require significant set-up time. In addition, their large size usually requires them to have a transfer line connecting the syringe to the reaction mixture, creating the problem of reagent material being trapped in the transfer lines.
The company J-Kem® sells a multiple component system consisting of three separate devices that will control a syringe based on temperature or pH, however this system is bulky, requires electrical cords, and is not portable. No prior art syringe pump is available as a single, hand-held device capable of monitoring physical properties of the reaction mixture such as temperature and/or ion content thereof, and then altering the programmed addition rate of the reagent to the reaction mixture according to these physical properties.
Therefore, while currently available prior art syringe pumps may fulfill their respective, particular objectives, a further need exists for a single automated device that is adapted not only to control the automated dispensing of reagent from a syringe but also to sense physical properties of the reaction mixture such as temperature and/or ion content as the reagent is being added. Also, a need exists for a syringe pump that is able to automatically adjust the addition rate of the reagent as is necessary according to changes in the reaction mixture over time. Further, a need exists to incorporate a syringe pump with temperature and ion sensing capabilities into a single device small enough to easily fit under a reaction hood in a laboratory.